Arabian oryx

The Arabian oryx (Oryx leucoryx) or white oryx is a medium-sized antelope with a distinct shoulder bump, long, straight horns, and a tufted tail.[2] It is a bovid, and the smallest member of Oryx genus, native to desert and steppe areas of the Arabian Peninsula. The Arabian oryx was extinct in the wild by the early 1970s, but was saved in zoos and private preserves and reintroduced into the wild starting in 1980.

In 1986, the Arabian oryx was classified as endangered on the IUCN Red List, and in 2011 it was the first animal to revert to Vulnerable status after previously being listed as extinct in the wild. It is listed in CITES Appendix I. In 2011, populations were estimated at over 1000 individuals in the wild, and 6000–7000 individuals in captivity worldwide.

A Qatari oryx named "Orry" was chosen as the official games mascot for the 2006 Asian Games in Doha,[3] and is shown on tailwings of planes belonging to Middle Eastern airline Qatar Airways.

Etymology

The taxonomic name Oryx leucoryx is from the Greekorux (gazelle or antelope) and leukos (white). The Arabian oryx is also called the white oryx in English, and is known as maha, wudhaihi, baqar al wash, and boosolah in Arabic.[4]

Anatomy and morphology

An Arabian oryx stands about 1 m (39 in) high at the shoulder and weighs around 70 kg (150 lb). Its coat is an almost luminous white, the undersides and legs are brown, and black stripes occur where the head meet the neck, on the forehead, on the nose and going from the horn down across the eye to the mouth. Both sexes have long, straight or slightly curved, ringed horns which are 50 to 75 cm (20 to 30 in) long.

Arabian oryx rest during the heat of the day and can detect rainfall and will move towards it, meaning they have huge ranges; a herd in Oman can range over 3,000 km2 (1,200 sq mi). Herds are of mixed sex and usually contain between two and 15 animals, though herds of up to 100 have been reported. Arabian oryx are generally not aggressive toward one another, which allows herds to exist peacefully for some time.[5]

Other than humans, wolves are the Arabian oryx's only predator. In captivity and good conditions in the wild, oryx have a life span of up to 20 years.[6] In periods of drought, though, their life expectancy may be significantly reduced by malnutrition and dehydration. Other causes of death include fights between males, snakebites, disease, and drowning during floods.[7]

Distribution and habitat

Historically, the Arabian oryx probably ranged throughout most of the Middle East. In the early 1800s, they could still be found in the Sinai, Israel, the Transjordan, much of Iraq, and most of the Arabian Peninsula. During the 19th and early 20th centuries, their range was pushed back towards Saudi Arabia, and by 1914, only a few survived outside that country. A few were reported in Jordan into the 1930s, but by the mid-1930s, the only remaining populations were in the Nafud Desert in northwestern Saudi Arabia and the Rub' al Khali in the south.[2]

In the 1930s, Arabian princes and oil company clerks started hunting Arabian oryx with automobiles and rifles. Hunts grew in size, and some were reported to employ as many as 300 vehicles. By the middle of the 20th century, the northern population was effectively extinct.[2] The last Arabian oryx in the wild prior to reintroduction were reported in 1972.[8]

Arabian oryx prefer to range in gravel desert or hard sand, where their speed and endurance will protect them from most predators, as well as most hunters on foot. In the sand deserts in Saudi Arabia, they used to be found in the hard sand areas of the flats between the softer dunes and ridges.[2]

Arabian oryx have been reintroduced to Oman, Saudi Arabia, Israel, United Arab Emirates, and Jordan. A small population was introduced on Hawar Island, Bahrain and large semimanaged populations at several sites in Qatar and the UAE. The total reintroduced population is now estimated to be around 1,000. This puts the Arabian oryx well over the threshold of 250 mature individuals needed to qualify for Endangered.[1]

Ecology

Feeding ecology

Arabian oryx, Antelope Ranch, Israel

The diets of the Arabian oryx consist mainly of grasses, but they will eat a large variety of vegetation, include trees, buds, herbs, fruit, tubers and roots. Herds of Arabian oryx follow infrequent rains to eat the new plants that grow afterward. They can go several weeks without water.[5] Research in Oman has found grasses of the genus Stipagrostis are primarily taken; flowers from Stipagrostis plants appeared highest in crude protein and water, while leaves seemed a better food source with other vegetation.[9]

Behavioral ecology

When the oryx is not wandering its habitat or eating, it digs shallow depressions in soft ground under shrubs or trees for resting. They are able to detect rainfall from a distance and follow in the direction of fresh plant growth. The number of individuals in herd can vary greatly (up to 100 have been reported occasionally), but the average is 10 or fewer individuals.[10] Bachelor herds do not occur, and single territorial males are rare. Herds establish a straightforward hierarchy that involves all females and males above the age of about seven months.[11] Arabian oryx tend to maintain visual contact with other herd members, subordinate males taking positions between the main body of the herd and the outlying females. If separated, males will search areas where the herd last visited, settling into a solitary existence until the herd's return. Where water and grazing conditions permit, male oryx establish territories. Bachelor males are solitary.[6] A dominance hierarchy is created within the herd by posturing displays which avoid the danger of serious injury their long, sharp horns could potentially inflict. Males and females use their horns to defend the sparse territorial resources against interlopers.[12]

Unicorn myth

The mythical unicorn may have originated in part from the Arabian oryx, which can appear to have only one horn when seen in profile.[13]

An alternative origin of the mythical one-horned unicorn may have been from sightings of an injured oryx; Aristotle and Pliny the Elder held that the oryx was the unicorn's "prototype".[14] From certain angles, the oryx may be mistaken as having one horn instead of two,[15] and given that its horns are made from hollow bone which cannot be regrown, if an oryx were to lose one of its horns, for the rest of its life it would have only one horn.[14]

Conservation

Arabian oryx in Zoo Dvůr Králové, Czech Republic

The Phoenix Zoo and the Fauna and Flora Preservation Society of London (now Fauna and Flora International), with financial help from the World Wildlife Fund, are credited with saving the Arabian oryx from extinction. In 1962, these groups started the first captive-breeding herd in any zoo, at the Phoenix Zoo, sometimes referred to as "Operation Oryx".[16][17] Starting with 9 animals, the Phoenix Zoo has had over 200 successful births. From Phoenix, oryx were sent to other zoos and parks to start new herds.

In June 2011, the Arabian oryx was relisted as vulnerable by the IUCN Red List. The IUCN estimated more than 1000 Arabian oryx in the wild, with 6000–7000 held in captivity worldwide in zoos, preserves, and private collections. Some of these are in large, fenced enclosures (free-roaming), including those in Syria (Al Talila), Bahrain, Qatar, and UAE.[1] This is the first time the IUCN has reclassified a species as vulnerable after it had been listed as extinct in the wild.[20] The Arabian oryx is also listed in CITES Appendix I.[21]

On June 28, 2007, Oman's Arabian Oryx Sanctuary was the first site ever to be removed from the UNESCOWorld Heritage List. UNESCO's reason for this was the Omani government's decision to open 90% of the site to oil prospecting. The Arabian oryx population on the site has been reduced from 450 in 1996 to only 65 in 2007. Now, fewer than four breeding pairs are left on the site.[22]